The present invention relates to microwave devices in general. In particular, it concerns compact, efficient microwave devices for heating liquids.
It is known to use electromagnetic radiation of microwave frequencies to heat various materials, including water and other liquids.
Conventional microwave heating devices have three elements: a microwave generator, a waveguide, and an applicator. The microwave generator, which may be any of a number of types, produces microwaves of a frequency or range of frequencies suited to the material to be heated. The waveguide is coupled at one end to the microwave generator and at the other to the applicator so that radiation passes to the applicator which contains the material to be heated. Depending on the type of material to be heated, the applicator may be a cavity, as in a domestic microwave oven, or an extended waveguide through which the material to be heated is passed.
Conventional microwave heating devices have two major disadvantages. Firstly, the need for a separate waveguide and applicator in addition to the microwave generator limits the minimum size and cost of the device. And secondly, coupling losses both between the microwave generator and the waveguide, and between the waveguide and the applicator, reduce the efficiency of the device. Furthermore, most conventional microwave generators require a high-voltage power supply which leads to a high cost of manufacture.
There is therefore a need for compact, efficient microwave devices for heating liquids which overcomes the aforementioned shortcomings of the prior art.